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Add column with constant value to pandas dataframe [duplicate]
...lumn is because df.index and the Index of your right-hand-side object are different. @zach shows the proper way to assign a new column of zeros. In general, pandas tries to do as much alignment of indices as possible. One downside is that when indices are not aligned you get NaN wherever they aren't...
Retrieve only static fields declared in Java class
...s = new ArrayList<Field>();
for (Field field : declaredFields) {
if (java.lang.reflect.Modifier.isStatic(field.getModifiers())) {
staticFields.add(field);
}
}
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Test whether a glob has any matches in bash
If I want to check for the existence of a single file, I can test for it using test -e filename or [ -e filename ] .
19 ...
Jinja2 shorthand conditional
...
Yes, it's possible to use inline if-expressions:
{{ 'Update' if files else 'Continue' }}
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How do you execute an arbitrary native command from a string?
...mpt:
$command = 'C:\somepath\someexe.exe somearg'
iex $command
However, if the exe is in quotes, you need the help of & to get it running, as in this example, as run from the commandline:
>> &"C:\Program Files\Some Product\SomeExe.exe" "C:\some other path\file.ext"
And then in th...
Math.random() explanation
...sive, ie [2,5], and min must be less than max in the above example.
EDIT: If someone was going to try and be stupid and reverse min and max, you could change the code to:
int randomWithRange(int min, int max)
{
int range = Math.abs(max - min) + 1;
return (int)(Math.random() * range) + (...
How to get the first column of a pandas DataFrame as a Series?
...=================================================================
UPDATE
If you're reading this after June 2017, ix has been deprecated in pandas 0.20.2, so don't use it. Use loc or iloc instead. See comments and other answers to this question.
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What is the C# equivalent of NaN or IsNumeric?
... guess I can use Double.Parse or a regex (see below) but I was wondering if there is some built in way to do this, such as javascript's NaN() or IsNumeric() (was that VB, I can't remember?).
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How exactly does the python any() function work?
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If you use any(lst) you see that lst is the iterable, which is a list of some items. If it contained [0, False, '', 0.0, [], {}, None] (which all have boolean values of False) then any(lst) would be False. If lst also contain...
Converting file size in bytes to human-readable string
...FileSize(bytes, si=false, dp=1) {
const thresh = si ? 1000 : 1024;
if (Math.abs(bytes) < thresh) {
return bytes + ' B';
}
const units = si
? ['kB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB']
: ['KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB'];
let u = -1;...